终止由子进程执行的命令

Question

I have a python script which listens to specific stream and records it like this:

subprocess.call(['ffmpeg', '-y', '-i', 'udp://streamurl:streamport', '-acodec', 'copy', '-f', 'mp3', 'filename.mp3'])

Also it checks tcp connection on port 7777 (when stream is live it connects to this port on my pc) I want to terminate subprocess command every time connection on port 7777 closes. How can I do this?

Answer 1

subprocess.call() is a blocking call - it waits for the subprocess to finish.

You may want to use subprocess.Popen() instead, which returns a Popen object that you can interact with and terminate using Popen.terminate() .

See the documentation here .

Answer 2

from subprocess import Popen, STDOUT, PIPE
from time import sleep

def connected(sock):
    try:
        sock.send(b'')
    except:
        return False
    return True

handle = Popen(['ffmpeg', '-y', '-i', 'udp://streamurl:streamport', '-acodec', 'copy', '-f', 'mp3', 'filename.mp3'], shell=False, stdout=PIPE, stdin=PIPE, stderr=STDOUT)

output = ''
while handle.poll() is None and connected(socket): # No exit code given, ergo command still running
    output += handle.stdout.readline()
    sleep(0.025)

if not connected(socket):
    handle.terminate()

output += handle.stdout.read()
handle.stdout.close()
handle.stdin.close()
print(output)

Note : I have no clue what "socket" is but i'm assuming just a regular socket of sorts.
I'd like to point out that i'm by no means a perfect programmer but this would give you an idea of what you would need to do altho not perfect this would work :)